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 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
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 * Portions Copyrighted 2008 Sun Microsystems, Inc.
 */

package chana.jpql.rats;

import java.util.Stack;
import xtc.util.State;

/**
 *
 * @author Caoyuan Deng
 */
public class ParserState implements State {
    
    public static final int NL_ENABLE  = 0;
    public static final int NL_DISABLE = 1;    

    
    private Stack<Integer> newlineStates = new Stack<Integer>();
    
    public void enterNewlineEnable() {
        newlineStates.push(NL_ENABLE);
    }
    
    public boolean newlineEnable() {
        return newlineStates.empty() ? true : newlineStates.peek() == NL_ENABLE;
    }
    
    public void enterNewlineDisable() {
        newlineStates.push(NL_DISABLE);
    }
    
    public void exitNewlineDisable() {
        newlineStates.pop();
    }
    
    public boolean newlineDisable() {
        return ! newlineEnable();
    }

    public void exitNewlineEnable() {
        newlineStates.pop();
    }
    
    public void start() {
        
    }

    public void commit() {

    }

    public void abort() {
        
    }
    
    public void reset(String arg0) {
        newlineStates.clear();
    }

}



